Protection of electronic apparatus against static electricity and erroneous operations

ABSTRACT

An electronic apparatus, such as an on-vehicle navigation system, is provided. The apparatus comprises a hard disc container ( 2 ) and a contacting piece ( 31 ) for grounding. The hard disc container contains a hard disc unit ( 7 ) detachably loaded thereinto. A loading/unloading passage ( 21 ) through which the hard disc unit is loaded and unloaded is formed in the container. The contacting piece is disposed in the loading/unloading passage. When the hard disc unit is loaded into the container, the hard disc unit is made to come into contact to the contacting piece before an electrical connection between the hard disc and the hard disc container is realized. Thus, even if static electricity is charged on the hard disc unit, the static electricity is grounded steadily prior to the electrical connection, thereby no harm being given to data stored by a hard disc incorporated in the hard disc unit.

BACKGROUND OF THE INVEVENTION

[0001] 1. Technical Field

[0002] The present invention relates to an electronic apparatus, and inparticular, to an electronic apparatus equipped with a recording mediumcontainer into which a magnetic hard disc, which serves as a magneticrecording medium, is detachably contained.

[0003] 2. Related Art

[0004] Recently, a navigation system, which is an electronic apparatusthat can be handled directly by crews, mounted on a car has becomepopular. A conventional navigation system uses an information recordingmedium to store map data, which is for instance a CD (Compact Disc)-ROMor a DVD (Digital Video Disc or Digital Versatile Disc)-ROM. A recenttrial is that an information recording medium, such a CD-ROM or DVD-ROM,is replaced by an inexpensive, higher-memory-capacity, and rewritablehard disc (i.e., hard disc unit) to store map data therein.

[0005] In the case that the hard disc can be mounted, there are manyadvantages such that map data are easier to be updated because user'sindividual data as well as map data can be stored due to a largecapacity of the memory. On the other hand, a problem concerning staticelectricity has been pointed out. To be specific, it is frequentlyrequired that users have to remove a hard disc (i.e., a hard disc unit;a casing in which a hard disc medium is incorporated) from a navigationsystem to rewrite its old map data into new ones. The hard disc unit ofwhich map data have been updated is again loaded into the navigationsystem. During such unloading and loading operations, static electricitywill be to some extent accumulated on the user's body surface. Thestatic electricity is transferred and charged onto the outer surface ofthe hard disc unit, which may have undesired influence on data stored onthe hard disc.

[0006] If such charged hard disc unit is loaded, the electric charge onthe hard disc unit may create high voltage such hat it is applied toelectronic parts mounted on a substrate of the hard disc unit. Due tothe application of the high voltage, there is a possibility that theelectronic parts are damaged.

[0007] In addition, there is a drawback resulted from the fact that theconventional navigation system is provided with no means for preventingerroneous operations to its power supply. Usually, after removing adressed cover detachably placed at a disc insertion inlet of thenavigation system, a user unloads a hard disc unit therefrom to rewritenew map data to its hard disc. The user then loads the hard disc unitinto the navigation system, before attaching the dressed cover onto thedisc insertion inlet. In the absence of any means for preventingerroneous operations to the power supply of the navigation system, theforegoing unloading and loading operations may cause various problems.

[0008] A practical problem may arise when the hard disc unit is loadedor unloaded to or from the navigation system with the navigation systempowered. That is, such unloading or loading operations may happen tospoil data written on the hard disc. Moreover, it is pointed out that ifthe navigation system is powered with no hard disc unit loaded, thesystem may operate erroneously.

SUMMARY OF THE INVENTION

[0009] The present invention has been made with due consideration to theforegoing drawbacks, and a first object of the present invention is toprovide an electronic apparatus capable of avoiding a magnetic recordingmedium from being damaged due to static electricity when the medium isloaded into an objective system.

[0010] A second object of the present invention is to provide anelectronic apparatus that is able to protect data written on a magneticrecording medium as well as electronic parts from static electricityduring unloading or loading the medium from or to an objective system.

[0011] A third object of the present invention is to provide anelectronic apparatus and a method for controlling power supply, whichare able to protect data written on a magnetic recording medium fromerroneous procedures in loading the medium into an objective system andto prevent the objective system from operating erroneously.

[0012] In order to realize the above objects, as a first aspect, thepresent invention provides an electronic apparatus comprising: arecording medium container into which a recording medium unit isdetachably loaded and in which a guide passage for loading/unloading therecording medium unit is formed; and an earth-contacting member isdisposed in the guide passage.

[0013] In this configuration, even when a recording medium unit, such asa hard disc unit, charged with static electricity thereon is insertedinto a recording medium container, the static electricity can securelybe grounded via an earth-contacting member before the recording mediumunit is connected to a connector attached in the recording mediumcontainer. That is, the static electricity passes directly to the earth,with data stored in a recording medium protected. Additionally, thisgrounding of the static electricity prevents other electronic partsincorporated in the electronic apparatus from being damaged.

[0014] In the above configuration, preferably, the recording mediumcontainer is a casing made of conductive material and theearth-contacting member is disposed at a predetermined position aroundthe casing. It is also preferred that the earth-contacting member is acontacting piece formed on the casing, the contacting piece being madeto come in contact with an outer surface of the recording medium unit tobe loaded. By way of example, the casing has an insertion inlet throughwhich the recording medium unit is inserted and the contacting piece isformed in a vicinity of the insertion inlet. The recording medium unitis, for example, a hard disc unit including a hard disc on whichinformation is magnetically recorded.

[0015] As a second aspect, the present invention provides an electronicapparatus comprising: a recording medium container into which arecording medium unit is detachably loaded and that has an insertioninlet through which the recording medium unit is loaded thereinto; acover detachably attached to the insertion inlet of the recording mediumcontainer; a first detector configured to detect a first state in whichthe cover has removed from the insertion inlet; a second detectorconfigured to detect a second state in which the recording medium unithas unloaded from the recording medium container; and stopping meansconfigured to stop supplying power from a power supply to a load if atleast one of the first and second detectors detect at least one of thefirst and second states.

[0016] This configuration makes it possible that, when removal of thecover from the insertion inlet and/or unloading of the recording mediumfrom the container are detected through the first and second detectors,the power from a power supply is forcibly stopped to be supplied. Thus,when the recording medium unit is loaded or unloaded, data stored in itsrecording medium are protected from erroneous operations and theelectronic apparatus is also avoided from being erroneously operated.

[0017] In the above configuration, it is preferred that the detectorsare disposed in parallel at the insertion inlet. It is also preferredthat the cover has a protrusion formed thereon and the first detector isconfigured to selectively detect either one of a contact to theprotrusion and a non-contact from the protrusion. Still preferably, therecording medium has an overhanging member formed on a rear end of therecording medium and the second detector is configured to selectivelydetect either one of a contact to the overhanging member and anon-contact from the overhanging member.

[0018] Still, as a third aspect of the present invention, there isprovided a method for controlling power supply in an electronicapparatus comprising a recording medium container into which a recordingmedium unit is detachably loaded and that has an insertion inlet throughwhich the recording medium unit is loaded thereinto and a coverdetachably attached to the insertion inlet of the recording mediumcontainer, the method comprising the steps of: first detecting a firststate in which the cover has removed from the insertion inlet; seconddetecting a second state in which the recording medium unit has unloadedfrom the recording medium container; and stopping supplying power from apower supply to a load if at least one of the first and second states isdetected.

[0019] Thus, like the foregoing one, when the recording medium unit isloaded or unloaded, data stored in its recording medium are protectedfrom erroneous operations and the electronic apparatus is also avoidedfrom being erroneously operated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other objects and aspects of the present invention will becomeapparent from the following description and embodiments with referenceto the accompanying drawings in which:

[0021]FIG. 1 is a perspective view representing a navigation system towhich an example of an electronic apparatus according to the presentinvention is applied;

[0022]FIG. 2 is a front view of the navigation system;

[0023]FIG. 3A is a perspective view, viewed upward from under thenavigation system, representing a recording medium container disposed inthe navigation system;

[0024]FIG. 3B is another perspective view of the recording mediumcontainer, when viewing the recording medium container reversed;

[0025]FIG. 4 shows a perspective view of a connector incorporated in thenavigation system;

[0026]FIG. 5 is an enlarged front view of the connector;

[0027]FIG. 6 shows a cross section of the connector, taken along A-Aline in FIG. 5;

[0028]FIG. 7 is a side view of the connector;

[0029]FIG. 8 is a cross section showing a contacting piece formed on acasing of the recording medium container;

[0030]FIG. 9 is an illustration of two switches attached to the vicinityof an opening formed by a hard disc insertion inlet of the navigationsystem; and

[0031]FIG. 10 is a circuit diagram showing a power supply protectingcircuit that employs the two switches.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

[0032] Refereeing to the accompanying drawings, a preferred embodimentof the present invention will now be described. The present inventionwill be descried about an on-vehicle navigation system to which anelectronic apparatus according to the present invention is applied.

[0033]FIG. 1 shows a navigation system to which one embodiment of anelectronic apparatus according to the present invention is applied, andFIG. 2 is a front view of the navigation system. The navigation systemshown by FIGS. 1 and 2 has a not-shown front cover secured on a frontpanel thereof, but the navigation system is shown with the front coverremoved, the front cover being able to be opened and closed freely.

[0034] As shown in FIG. 1, the navigation system includes a rectangular,box-like bottomed frame 1, which is for example incorporated within arecessed portion of the dashboard of a vehicle. In the inner spacing ofthe frame 1, there is a hard disc container serving as a recordingmedium container, a PC card container 3, and a substrate/fan container4. Though not shown, a compact card type of magnetic recording medium(hereafter, referred to as a PC card), which is frequently called memorycard, can be inserted into the PC card container 3. This PC cardcontainer 3 is positioned next to the hard disc container 2, while thesubstrate/fan container 4 is positioned at the side of the rears of boththe hard disc container 2 and the PC card container 3.

[0035] A ROM drive unit (not shown) to drive a CD-ROM or DVD-ROM ismounted above both of the hard disc container 2 and the PC cardcontainer 3.

[0036] The PC card, which serves as the foregoing card type of recordingmedium, can be used for storing information at both a home-use personalcomputer and the navigation system according to the present embodiment.Also, among a plurality of electronic apparatuses, the PC card can beused as a common recording medium to record pieces of information. Onthe front of the frame 1, a front panel 5 is secured as shown in FIGS. 1and 2. The front panel 5 can be seen after the front cover is removed.At the lower left of the front panel 5, a dressed cover 6 is disposed.When the dressed cover 6 is removed, a hard disc insertion inlet 9 toload and unload two hard disc units 7 and 8 serving as magneticrecording medium units of the present invention can be seen. The harddisc units 7 and 8 include therein hard discs 7 h and 8 h, respectively.The hard disc insertion inlet 9 is continuously coupled with the harddisc container 2. In FIG. 2, the navigation system is shown with the twohard disc units 7 and 8 unloaded.

[0037] In the configuration shown in FIG. 1, one hard disc unit 7memorizes various types of data, such as map data and individual musicdata, while the remaining hard disc unit 8 memorizes data of, forexample, music information recorded by a user for private use. The frontpanel 5 is formed to be almost perpendicular to the running direction ofthe vehicle.

[0038] On both the longitudinal sides of each of the hard disc units 7and 8, as shown in FIG. 1, rod-like slide members 7 a (8 a) are securedalong their sides. In addition, on the front side to be inserted aheadof each hard disc unit 7 (8), pluralities of pins 7 b (8 b) to beconnected with a later-described connector are built. An overhangingpiece 7 c is fixedly arranged at one side end of the rear of the harddisc unit 7 to extend in its width direction thereof. On the rear ofeach of the hard disc units 7 and 8, an insulating and flexible handle 7d (8 d) made of plastic material is mounted for holding in loading andunloading each hard disc unit 7 (8).

[0039] At the frontal lower right of the front panel 5, a card insertioninlet 10 with a cover is formed, through which the not-shown PC card isloaded and unloaded. The cover can be opened when such loading andunloading is needed. The card insertion inlet 10 is continuously led tothe PC card container 3. An ejection button 11 is arranged next to thecard insertion inlet 10 to eject the PC card.

[0040] Further, a ROM insertion inlet 12 is opened at the frontal upperlocation of the front panel 5 so as to load and unload the CD-ROM orDVD-ROM. The ROM insertion inlet 12 is continuously led to the driveunit to drive the ROM. A further ejection button 13 is placed next tothe ROM insertion inlet 12 so that the ROM can be ejected.

[0041] The hard disc container 2 includes a casing 15, as shown in FIGS.3A and 3B, which serves as a conductive case. The casing 15 is formed bybending a plate-like member, made of a conductive metal material such asstainless steel, into a flat box shape, but no bottom. That is, thecasing 15 is structured into one body including a ceiling portion 16 andwall portions 17 built at both ends of the ceiling portion 16.

[0042] On the inner side of each of the wall portions 17, a rail member18 is secured along the longitudinal direction thereof in such a mannerthat the rail members 18 on both the wall portions17 are paired face toface. In each of the rail members 18, two upper and lower guide grooves19 and 20 are formed along the longitudinal direction of each railmember. The foregoing slide members 7 a (8 a) on both the sides of eachhard disc unit 7 (8) can be inserted into the guide grooves 19 (20), andslid therealong with its guide, so that each of the hard disc units 7and 8 can be loaded and unloaded. Thus, a spacing surrounded by both thepair of rail members 18 and the ceiling portion 16 functions as aloading/unloading passage 21 for the hard disc unit 7.

[0043] Moreover, at the hard disc insertion inlet 9, the upper partitionconstituting the upper guide groove 19 together with its lower partitionshown in FIG. 3A is bent in the form of an arc (refer to FIGS. 3A and3B). Also, at the hard disc insertion inlet 9, the upper partitionconstituting the lower guide groove 20 together with its lower partitionin FIG. 3A is formed to be an oblique shape. Both of the arc form andoblique shape make it easier to insert the slide members 7 a and 8 a ofthe hard disc units 7 and 8 into the individual guide grooves 19 and 20.

[0044] On the inner rear of the casing 15, a substrate 22 is mounted,and two connectors 23 are secured to lateral upper and lower locationson the substrate 22. Each connector 23 is equipped with a body 24 madeof heat-resistance resin and fastened on the substrate 22 and a covermember 25 formed in an approximately M-shaped in section, made ofheat-resistance resin, and attached to the body 24 so that the covermember 25 can be swung. When each of the hard disc units 7 and 8 isinserted into the guide grooves 19 (20), the pins 7 b (8 b) of each harddisc unit 7 (8) are inserted into the cover member 25.

[0045] With reference to FIGS. 4 to 7, the structure of each connector23 will be detailed.

[0046] As shown in FIGS. 4 to 7, the body 24 of each connector 23 isformed into an approximately U-shape in section and standing-up walls 24a are integrally formed on both sides of the body 24 (refer to FIGS. 4,5 and 7). Through the root of each standing-up wall 24 a, a slit 24 b isformed. On the other hand, the cover member 25 of each connector 23 isshaped into an approximately M-form in section, in which a plurality ofthrough holes 25 a into which a plurality of pins 7 b or 8 b areinserted are formed therethrough. At both lower ends of sides of eachcover member 25, protrusions 25 b are formed to protrude in thelongitudinal direction of the cover member 25. Each protrusion 25 isfitted with each slit 24 b of the body 24.

[0047] As shown in FIG. 6, contact members 26 are placed through boththe body 24 and the cover member 25. Each contact member 26 made of agold-plated copper-based alloy is placed, one by one, toward eachthrough hole 25 a of the cover 25. One end of each contact member 26extends up to almost each through hole 25 a, while the other end thereofis taken out from the body 24 to be secured on the substrate by means ofsoldering. Thus, in cases where the pins 7 b and 8 b of the hard discunits 7 and 8 are inserted into the through holes 25 a of the covermember 25, the pins 7 b and 8 b realize electrical contacts with thesubstrate 22 via the contact members 26.

[0048] The cover member 25 is mounted to the body 24 with a slightspacing 27 left therebetween, wherein the protrusions 25 a of each covermember 25 are fitted to the slits 24 b of each body 24 and the pluralcontact members 26 are placed through both the body 24 and the covermember 25. Hence the cover member 25 is coupled with the body 24 as asingle structure, but can be swung in a direction shown by an arrow inFIG. 6.

[0049] As shown in FIGS. 3A and 3B, at a certain location near to thehard disc insertion inlet 9 on the ceiling portion 16 of the casing 15,an approximate U-shaped notch 30 is formed. A contacting piece 31, whichserves as a grounding contact member, is formed integrally with thenotch 30 such that the contacting piece 31 slightly protrudes downwardfrom the ceiling portion 16. Therefore, as illustrated in FIG. 8, whenthe hard disc unit 7 is inserted into the guide grooves 19, thecontacting piece 31 will come into contact with the upper surface of thehard disc unit 7. This contact permits static electricity charged on thehard disc unit 7 to be grounded via the casing 15 to the frame 1, beforethe pins 7 b of the hard disc unit 7 reach the through holes 25 b of thecover member 25.

[0050] Further, as shown in FIG. 2, at predetermined end positions onthe edge forming the hard disc insertion inlet 9, two switches 33 a and33 b are arranged in line in the up-and-down direction. One switch 33 aserves a first detector and the other switch 33 b serves a seconddetector. These switches 33 a and 33 b have, as shown in FIG. 9, bodies34 a and 34 b and operating pins 35 a and 35 b extendably protrudingforward from the bodies 34 a and 34 b, respectively. When each operatingpin 35 a (35 b) is pressed to retract into each body 34 a (34 b), theswitch 33 a (33 b) is turned on, whereas when each operating pin 35 a(35 b) is relieved from being pressed, thus being restored to itsprotruded position, the switch 33 a (33 b) is turned off.

[0051] As shown in FIG. 9, design is made such that when the dressedcover 6 is mounted onto the hard disc insertion inlet 9, a protrusion 6a formed on the rear of the dressed cover 6 pushes the operating pins 35a to retract into its body 34 a. Hence, the switch 33 a (the firstdetector) is turned on. In contrast, when the dressed cover 6 isremoved, the operating pin 35 a becomes protruded from the body 34 a,which makes the switch 33 a turn off.

[0052] In addition, the switch 33 b (the second detector) is mountedsuch that, when the hard disc unit 7 is inserted along the guide grooves19 and its pins 7 b are inserted into the through holes 25 a of thecover member 25 of the connector 23, the overhanging piece 7 c mountedon the rear of the hard disc unit 7 pushes the operating pin 35 b of theswitch 33 b. This makes the switch 33 b turn on. In response to pullingthe hard disc unit 7 from the guide grooves 19, the overhanging piece 7c separates from the switch 33 b. In response to this separation, theoperating pin 35 b restores to its protruded position, so that theswitch 33 b turns off.

[0053] As described, one switch 33 a is in charge of detecting a contactor non-contact of the protrusion 6 a mounted on the dressed cover 6 tothe hard disc insertion inlet 9. The other switch 33 b is in charge ofdetecting a contact or non-contact of the overhanging piece 7 c mountedon the rear of the hard disc unit 7.

[0054]FIG. 10 shows circuitry for protecting the power supply to whichboth the switches 33 a and 33 b are electrically connected.

[0055] As shown in FIG. 10, the switches 33 a and 33 b are connected inseries to a load 36 consisting of one ore more drive units and connectedto a backup power supply 38 via a main swatch 37, so that a seriallyconnected loop 39 is formed among the switches 33 a, 33 b and 37, load36, and backup power supply 38. This serially connected loop 39functions as stopping means of the present invention.

[0056] In the power supply protecting circuit, as long as any one of theswitches 33 a and 33 b is off, the turn-on of the main switch 37 willnot allow the backup power supply 38 to supply power to the load 36.Thus the load 36 will not be activated. The load 36 is not powered bythe backup power supply 38 and is not driven, unless both of theswitches 33 a and 33 b become turned on.

[0057] The navigation system of this embodiment will now be described interms of its operations.

[0058] It is frequently required that map data stored in the navigationsystem be rewritten for update. For the update, a user is requested toremove the dressed cover 6, and holds the handle 7 d of the hard discunit 7 contained in the hard disc container 2 so that it is pulled outthrough the hard disc insertion inlet 9. Then the map data are rewrittenfor update.

[0059] On removing the dressed cover 6, the operating pin 35 a of theswitch 33 a extends outward, thus being turned off. Additionally, ondrawing the hard disc unit 7 out from the hard disc insertion inlet 9,the overhanging piece 7 c of the hard disc unit 7 separates from theswitch 33 b, so that its operating pin 35 b extends outward to cause theswitch 33 b to turn off.

[0060] The user, who holds the handle 7 d of the updated hard disc unit7, then inserts it into the hard disc container 2 through the hard discinsertion inlet 9. During this insertion, the slide members 7 a of thehard disc unit 7 are guided by the guide grooves 19 of the rail members18 and slid therealong. The hard disc unit 7 slides with its uppersurface in contact with the contacting piece 31. Thus, even when staticelectricity charged on the user is transferred to the hard disc unit 7,the charged static electricity on the hard disc unit 7 is obliged toflow to the frame 1 via the casing 15, before the pins of the hard discunit 7 are inserted into the through holes 25 a of the connector 23.That is, the charged static electricity is grounded directly to thedashboard of the vehicle through the frame 1.

[0061] When the pins 7 b of the hard disc unit 7 have been inserted intothe through holes 25 a of the connector 23, the overhanging piece 7 c onthe rear of the hard disc unit 7 presses the operating pin 35 b of theswitch 33 b, so that the switch 33 b is turned on.

[0062] Finally, the dressed cover 6 is attached to the hard discinsertion inlet 9 as shown in FIG. 9, the protrusion 6 a on the rear ofthe dressed cover 6 pushes the operating pin 35 a of the switch 33 a.This causes the switch 33 a to turn on. Therefore, whenever the mainswitch is turned on after the turn-on of both the switches 33 a and 33b, the backup power supply 38 is finally allowed to supply power to theload 36. This makes it possible to actuate the various drive unitsincorporated in the navigation system.

[0063] In this embodiment, the switches 33 a and 33 b are mutuallyconnected in series, so that the backup power supply 38 is prohibited tosupply power to the load 36 until the turn-on of both the switches isrealized. The reason for the serial connection is as follows. Forexample, in cases where the switch 33 a is disposed alone, onlyattaching the dressed cover 6 to the hard disc insertion inlet 9 allowsthe backup power supply 38 to operate to supply power to the load 36,even if the hard disc unit 7 has not been inserted in the hard disccontainer 2 yet. This gives rise to an inconvenience that the driveunits operate without the hard disc unit 7. On the other hand, thearrangement of only the switch 33 b will cause an undesirable situationunder which the power supply from the backup power supply 38 to theloads 36 are still kept, even though the dressed cover 6 has alreadybeen removed. In the present embodiment, the foregoing inconveniencescan be avoided by arranging the two switches mutually connected inseries.

[0064] The present invention is not restricted to the foregoingembodiment, but can be reduced into practice in other variousmodifications. For example, the foregoing embodiment has adopted thecontacting piece 31 (functioning as an earth-contacting member) arrangedon the ceiling portion of the casing 15, but near to the hard discinsertion inlet 9. The contacting piece 31 is not limited to be arrangedin such a position. As long as the contacting piece 31 can be groundedto the frame 1, it can be arranged at any position, such as a positionin the loading/unloading passage 21 for the hard disc unit 7.Alternatively, the earth-contacting member is not always restricted tothe shape of a claw, but may be formed as a linearly shaped piece.

[0065] Further, the earth-contacting member according to the presentinvention may be arranged for the hard disc unit 8, not limited to theconfiguration for the hard disc unit 7 described in the foregoingembodiment. Specifically, such earth-contacting member may be arrangedin the loading/unloading passage 21 through which the hard disc unit 8is inserted or ejected, so that, even when the hard disc unit 8 isloaded into the hard disc container 2 by an operator who is charged withstatic electricity, static electricity charged on the hard disc unit 8is grounded through the earth-contacting member before the pins 8 b ofthe hard disc unit 8 have inserted into the through holes 25 a of theconnector 23.

[0066] Another modification is concerned with the arrangement of theswitches 33 a and 33 b. Although the forgoing embodiment has adopted thetwo switches 33 a and 33 b placed at the hard disc insertion inlet 9 inparallel in the up-and-down direction, they can be placed in theloading/unloading passage 21 that allows the hard disc unit 7 to beinserted or ejected. This mounting allows the switches 33 a and 33 b toturn on when the hard disc container 2 is loaded with the hard disc unit7.

[0067] There is still provided another modification about the number ofhard discs to be contained in the hard disc container 2. The foregoingembodiment has been described about the two hard disc units 7 and 8 thatcan be loaded into the hard disc container 2. Only one hard disc unit,that is, the hard disc unit 7 assigned to storage of map data andprivate-use music information data may be loaded into the hard disccontainer 2. Alternatively, if necessary, design to contain three ormore hard disc units is also possible.

[0068] Accordingly, the electronic apparatus described in the foregoingembodiment and its modifications is able to have various advantages.First, the contacting piece 31 serving as the earth-contacting member isdisposed in the loading/unloading passage 21 for the hard disc unit 7.Hence, even when the hard disc container 2 is loaded with the hard discunit 7 charged thereon with static electricity due to being handled by acrew who is charged with the static electricity, the static electricitycharged on the hard disc unit 7 is securely grounded through thecontacting piece 31 before the hard disc unit 7 is coupled with theconnector 23. The data themselves stored in the hard disc unit 7 can beprotected from the static electricity. In addition, other electronicparts can be avoided from receiving high voltage resulting from sparkscaused by the static electricity.

[0069] Since map data required for the navigation system is previouslystored in the hard disc unit 7, the map data can be protected from beingdamaged by the static electricity. Additionally, when updating the mapdata of the hard disc unit 7, unloading and loading the hard disc unit 7from and into the hard disc container 2 can be done with no electricinfluence on the main electric circuit of the system.

[0070] The contacting piece 31 is designed to be disposed on the casingto contain the hard disc unit 7. It is therefore possible to make thedisposal of the contacting piece 31 easier in its manufacture. Still,the contacting piece 31 formed on the casing 15 comes into contact withthe outer surface of the hard disc unit 7 inserted into the container 2.This also makes it possible that the static electricity charged on thehard disc unit 7 via the contacting piece 31 is grounded in an easierand securer manner prior to the connection of the hard disc unit 7 tothe connector 23.

[0071] Furthermore, the contacting piece 31 is disposed nearer to thehard disc insertion inlet 9 on the casing 15. This makes it longer adistance (i.e., time) to allow the contacting piece 31 to contact thehard disc unit 7 during the insertion of the hard disc unit 7. Groundingthe hard disc unit 7 can therefore be steadier.

[0072] The insulating-material-made handles 7 d and 8 d that a user isable to grasp for insertion and ejection of the hard disc units 7 and 8are attached to the hard disc units 7 and 8, respectively. Thus, evenwhen a user who is charged with static electricity handles the hard discunits 7 and 8, the handles 7 d and 8 d are reluctant to an easiertransfer of the static electricity from the user to the hard disc units7 and 8.

[0073] Each of the connectors 23 is made into one unit by fitting thecover 25 to the body 24 with the slight spacing 27 left therebetween andwith the contact member 26 made to intervene therebetween, so that thecover 25 can be swung against the body 24. Therefore, if the pins 7 b (8b) of the hard disc unit 7 (8) are positionally deviated to some extentfrom the through holes 25 a of the connector 23 when the hard disc unit7 (8) is inserted, the deviation can be absorbed by swings of the cover.Thus the hard disc unit 7 (8) can be inserted into the connector 23 withease, facilitating user's operations necessary for such insertion.

[0074] On the other hand, in the foregoing embodiment, removing thedressed cover 6 from the hard disc insertion inlet 9 is detected by oneswitch 33 a and unloading the hard disc unit 7 from the hard disccontainer 2 is detected by the other switch 33 b. When at least one ofthe switches 33 a and 33 b is turned on, the backup power supply 38 isforcibly stopped to supply the power. Accordingly, if the hard disc unit7 is inserted in a mistaken operation order, the electronic influence onthe main circuit of the system can be avoided by the above automaticstop of the power supply. It is therefore possible to protect datastored in the hard disc unit 7 during the insertion and ejection thereofand erroneous operations toward the navigation system can be preventedsteadily.

[0075] In addition, the switches 33 a and 33 b are disposed in parallelat the hard disc insertion inlet 9, so that they can be attached in aneasier manner when being manufactured.

[0076] Further, of the two switches 33 a and 33 b, one is disposed todetect contacts to the protrusion 6 a formed on the dressed cover 6 andthe other is disposed to detect contacts to the overhanging piece 7 c atthe rear of the hard disc unit 7. This disposal makes it possible toraise accuracy of the detection of the switches 33 a and 33 b.

[0077] The present invention may be embodied in other specific formswithout departing from the spirit or essential characteristics thereof.The present embodiments are therefore to be considered in all respectsas illustrative and not restrictive, the scope of the present inventionbeing indicated by the appended claims rather than by the foregoingdescription and all changes which come within the meaning and range ofequivalency of the claims are therefore intended to be embraced therein.

[0078] The entire disclosure of two Japanese Patent Application Nos.2001-136412 and 2001-136413 both filed on May 7, 2001 including thespecification, claims, drawings and summary is incorporated herein byreference in its entirety.

What is claimed is:
 1. An electronic apparatus comprising: a recordingmedium container into which a recording medium unit is detachably loadedand in which a guide passage for loading/unloading the recording mediumunit is formed; and an earth-contacting member is disposed in the guidepassage.
 2. The electronic apparatus of claim 1, wherein the recordingmedium container is a casing made of conductive material and theearth-contacting member is disposed at a predetermined position aroundthe casing.
 3. The electronic apparatus of claim 2, wherein theearth-contacting member is a contacting piece formed on the casing, thecontacting piece being made to come in contact with an outer surface ofthe recording medium unit to be loaded.
 4. The electronic apparatus ofclaim 3, wherein the casing has an insertion inlet through which therecording medium unit is inserted and the contacting piece is formed ina vicinity of the insertion inlet.
 5. The electronic apparatus of claim1, wherein the recording medium unit is a hard disc unit including ahard disc on which information is magnetically recorded.
 6. Anelectronic apparatus comprising: a recording medium container into whicha recording medium unit is detachably loaded and that has an insertioninlet through which the recording medium unit is loaded thereinto; acover detachably attached to the insertion inlet of the recording mediumcontainer; a first detector configured to detect a first state in whichthe cover has removed from the insertion inlet; a second detectorconfigured to detect a second state in which the recording medium unithas unloaded from the recording medium container; and stopping meansconfigured to stop supplying power from a power supply to a load if atleast one of the first and second detectors detect at least one of thefirst and second states.
 7. The electronic apparatus of claim 6, whereinboth of the detectors are disposed in parallel at the insertion inlet.8. The electronic apparatus of claim 6, wherein the cover has aprotrusion formed thereon and the first detector is configured toselectively detect either one of a contact to the protrusion and anon-contact from the protrusion.
 9. The electronic apparatus of claim 6,wherein the recording medium has an overhanging member formed on a rearend of the recording medium and the second detector is configured toselectively detect either one of a contact to the overhanging member anda non-contact from the overhanging member.
 10. A method of controllingpower supply in an electronic apparatus comprising a recording mediumcontainer into which a recording medium unit is detachably loaded andthat has an insertion inlet through which the recording medium unit isloaded thereinto and a cover detachably attached to the insertion inletof the recording medium container, the method comprising the steps of:first detecting a first state in which the cover has removed from theinsertion inlet; second detecting a second state in which the recordingmedium unit has unloaded from the recording medium container; andstopping supplying power from a power supply to a load if at least oneof the first and second states is detected.